How are thieves using OnStar to steal Yukons?

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swathdiver

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Makes sense. So what computer are they changing? And are they disabling the OnStar under the hood or inside the vehicle? Would locking the hood keep them from changing the computer or disabling onstar?
The Onstar module is inside the dashboard. They will typically pull out the radio or glovebox to access it and simply unplug it. As Wes said, they pop the hood, put in a different engine computer and drive away. There is nothing under the hood to do with Onstar AFAIK, not on any generation truck I'm familiar with anyway.

Put in a kill switch to your fuel pump and disguise it in some creative way. Airline pilots have a switch in the overhead to flip if they get hi-jacked that sends out the "We've been hi-jacked" signal.

What I do not understand is how they were able to bypass the ignition without a key? Keyless systems are easier to defeat but the keyed cars have another, physical layer of security that has to be defeated.

I keep looking, found this on the K2s:
Be sure to read the comments, more nuggets...

Cool info for the GMT800 guys in the comments...
 
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Samson518

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I’m in the northern Virginia area and after speaking with local police, for the newer cars with key fobs allowing unlock as you approach, remote start, etc., thieves use some sort of signal booster. They drive around with something that looks for the key fob signal being given off from in the house or wherever the key is, locks on and amplifies it, as if you are walking up to the truck with your key. Unlocks the door. I’m not sure if they use the fake/booster signal to continue to drive the vehicle for extended periods but they are able to drive off. It happens enough around here that Arlington County police advised homeowners to use a Faraday box to insulate the fobs and prevent signal leakage.
 

Rocket Man

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The Onstar module is inside the dashboard. They will typically pull out the radio or glovebox to access it and simply unplug it. As Wes said, they pop the hood, put in a different engine computer and drive away. There is nothing under the hood to do with Onstar AFAIK, not on any generation truck I'm familiar with anyway.

Put in a kill switch to your fuel pump and disguise it in some creative way. Airline pilots have a switch in the overhead to flip if they get hi-jacked that sends out the "We've been hi-jacked" signal.

What I do not understand is how they were able to bypass the ignition without a key? Keyless systems are easier to defeat but the keyed cars have another, physical layer of security that has to be defeated.

I keep looking, found this on the K2s:
Be sure to read the comments, more nuggets...

Cool info for the GMT800 guys in the comments...
Not sure about that GMT800 one, mine has Passlock as well as column lock. The time thieves got my cylinder to turn the column was still locked and the Passlock was not defeated. I still don’t understand why GM did away with column locks in newer vehicles though.
 

Doubeleive

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I’m in the northern Virginia area and after speaking with local police, for the newer cars with key fobs allowing unlock as you approach, remote start, etc., thieves use some sort of signal booster. They drive around with something that looks for the key fob signal being given off from in the house or wherever the key is, locks on and amplifies it, as if you are walking up to the truck with your key. Unlocks the door. I’m not sure if they use the fake/booster signal to continue to drive the vehicle for extended periods but they are able to drive off. It happens enough around here that Arlington County police advised homeowners to use a Faraday box to insulate the fobs and prevent signal leakage.
I don't think there are doing that with GM's but I could be wrong, I have seen that happen mostly to the Mercedes
 

Doubeleive

Wes
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The Onstar module is inside the dashboard. They will typically pull out the radio or glovebox to access it and simply unplug it. As Wes said, they pop the hood, put in a different engine computer and drive away. There is nothing under the hood to do with Onstar AFAIK, not on any generation truck I'm familiar with anyway.

Put in a kill switch to your fuel pump and disguise it in some creative way. Airline pilots have a switch in the overhead to flip if they get hi-jacked that sends out the "We've been hi-jacked" signal.

What I do not understand is how they were able to bypass the ignition without a key? Keyless systems are easier to defeat but the keyed cars have another, physical layer of security that has to be defeated.

I keep looking, found this on the K2s:
Be sure to read the comments, more nuggets...

Cool info for the GMT800 guys in the comments...
not sure what kind of aftermarket alarm this guy is saying won't work but the one I installed in my 2018 Silverado will
the moment they slimjim the door, break a window, jack it up, tow it away it triggers the key fob (if within a mile away), the 4g cellular function sends me a text, sends me a email and triggers a alarm on my phone app (anywhere worldwide)
it cost's about $1000.0+ (viper 5906v & smart start 4g plus extra sensors like tilt and glass break)
it is only defeatable if you do not respond to the alarm and just let them have it, they have to remove the starter kill and disconnect the 4g module which is buried behind and inside the dash
 

DougAMiller

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I don't think there are doing that with GM's but I could be wrong, I have seen that happen mostly to the Mercedes
I think they are doing this with most brands these days, but my understanding is that the newer passive remotes have a motion-detector so it doesn't transmit when sitting still in your home or office. This is to prevent them from intercepting the signal when the keys are just sitting on a desk or table, but it still doesn't stop them from picking it up as you walk away from the car. His neighbor saw thieves trying to steal my boss' Ferrari from his house that way last summer, but since the key was sitting still in the house, they couldn't do it.

You would think that they would require the BCM or other hard-to-get-to module to validate with the PCM before allowing it to start in order to prevent theft by swapping the PCM.

I guess it's like they say, if you build a better mouse trap, they'll make a smarter mouse.
 

Doubeleive

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I think they are doing this with most brands these days, but my understanding is that the newer passive remotes have a motion-detector so it doesn't transmit when sitting still in your home or office. This is to prevent them from intercepting the signal when the keys are just sitting on a desk or table, but it still doesn't stop them from picking it up as you walk away from the car. His neighbor saw thieves trying to steal my boss' Ferrari from his house that way last summer, but since the key was sitting still in the house, they couldn't do it.

You would think that they would require the BCM or other hard-to-get-to module to validate with the PCM before allowing it to start in order to prevent theft by swapping the PCM.

I guess it's like they say, if you build a better mouse trap, they'll make a smarter mouse.
on all of these GM's the "security" shuts off power to the fuel pump, that's it. how do you get around that? jumper the fuel pump relay
 

swathdiver

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not sure what kind of aftermarket alarm this guy is saying won't work but the one I installed in my 2018 Silverado will
the moment they slimjim the door, break a window, jack it up, tow it away it triggers the key fob (if within a mile away), the 4g cellular function sends me a text, sends me a email and triggers a alarm on my phone app (anywhere worldwide)
it cost's about $1000.0+ (viper 5906v & smart start 4g plus extra sensors like tilt and glass break)
it is only defeatable if you do not respond to the alarm and just let them have it, they have to remove the starter kill and disconnect the 4g module which is buried behind and inside the dash
When I saw this thread, I thought of you and the security system you have. Merry Christmas to you and yours Wes!
 

swathdiver

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Not sure about that GMT800 one, mine has Passlock as well as column lock. The time thieves got my cylinder to turn the column was still locked and the Passlock was not defeated. I still don’t understand why GM did away with column locks in newer vehicles though.
GMs reasoning for deleting the steering lock was because of the improved anti-theft features! They thought wrong on that one! The Escalades got the steering wheel lock back in 2010 and it further improved a year or two later. Merry Christmas Mark!
 

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